Processes, including chemical, mechanical, electrical, or human, involve numerous conditions having various measurements and data available. These measurements and data change constantly and their values are typically monitored or recorded using a computer system. Examples of such measurements may include temperature, pressure, on/off state, and resistance, to name a few. Using a computer system, these measurements may be subjected to specific gauging operations taking any number of selected measurements at any given time interval, particularly when monitoring or controlling a chemical process. The output of each gauge which reflects a measurement taken, may then be fed into a data base along with an identifier of the selected measurement, commonly called a tag. The data base may then be subjected to selected programs intended to provide the numerical analysis concerning the many parameters in the process. The output of such programs is desirably expressed in forms such as control charts and production record tables, or even video displays, which can then be scanned by the persons responsible for the manufacturing process. Upon the identification of a problem reflected in the representation of the parameters, the necessary corrective action can be identified and taken.
While such control processes represent an improvement over manual operations, there is little time for production personnel to review and interpret the data so that timely corrective action can be taken. This is especially true in chemical process monitoring, where a large number of individual elemental processes are being monitored, each of which is capable of causing a computer to generate data that must be reviewed before a control action can be taken. The production personnel are faced with the substantial problem of even identifying which of the information should be examined for possible problem identification. Due to the large amount of data, there are time delays in process error identification, and related delays in process correction, thus leading to reduced production, non-compliant goods, and/or other process inefficiencies.
Computer applications have also been used to apply simple logic to determine if certain predefined events have occurred based on the various measurements in a process. If events have occurred, then the event is communicated and a predefined action is taken, manual or automatic. In addition, other computer applications have been used to determine if certain process values and measurements are outside of a normal operating envelope. Some techniques that can be used to determine such aberrant conditions include stochastic process models, heuristically determined limits, and process design limits.
Even though such techniques are available, real-time analysis of multiple process dynamics present in a system is needed for better process control. Fast and clear identification of abnormal situations combined with the appropriate corrective actions, preferably without human intervention, would be beneficial.